As advanced structural materials, titanium alloys have found extensive applications in aerospace, medical devices, and precision electronics industries, serving as critical components for achieving lightweight designs in high-end equipment. In aerospace applications, titanium alloy components are frequently subjected to complex thermo-mechanical loading conditions involving varying temperature levels and multiaxial stress states, which may induce progressive fatigue damage accumulation and ultimately lead to premature fracture failures. This study conducts a systematic investigation into the fatigue damage mechanisms of aerospace-grade titanium alloys under service conditions, with particular emphasis on elucidating the synergistic effects of microstructural characteristics, surface integrity parameters, and operational temperature variations on fatigue behavior. Through comprehensive analysis, the research reveals that surface modification techniques, including shot peening (SP), ultrasonic surface polling process (USRP), and laser shock peening (LSP), significantly enhance fatigue performance through two primary mechanisms: (1) the generated residual compressive stress fields effectively inhibit crack initiation and retard propagation rates; (2) improved surface integrity characteristics, such as reduced roughness and work-hardened layers, contribute to enhanced oxidation resistance thereby preserving structural integrity.
This study introduces an innovative approach to enhancing the corrosion resistance and tribological performance of magnesium alloys by in situ growing zinc-aluminum layered double hydroxide (ZnAl-LDHs) with graphene oxide (GO) sealing. Traditional LDHs coatings exhibit limitations in corrosion protection due to their porous structure. This paper advances the LDHs coating technology by integrating GO, forming a composite LDHs/GO coating on magnesium alloys. The novel incorporation of GO provides a unique two-layered defense system against corrosion: the GO layer serves as a high-resistance barrier to corrosive agents, while the LDHs layer absorbs NO3− ions, offering a secondary protection. The coating’s properties were meticulously characterized using techniques such as scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Fourier-transform infrared (FTIR) Raman spectroscopy, electrochemical assays, and friction-wear tests. Experimental findings reveal that the synergistic action between LDHs and GO results in significant improvements in corrosion resistance and friction reduction. Specifically, GO’s adherence to the LDHs coating’s pores and its ability to transfer into the friction layer during wear significantly enhances the coating’s integrity and stability. The successful in situ synthesis of LDHs /GO coatings opens new horizons for composite coatings, with potential implications across various industrial applications.
The inhibition behavior of the promising eco-friendly inhibitor 8-hydroxyquinoline (8HQ) in two concentrations of sodium chloride solution was studied by hydrogen evolution, scanning electron microscope (SEM), three-dimensional morphology, electrochemical testing, and computational calculations. The results indicated that the 8HQ inhibitor showed satisfactory inhibition effect due to its fast, excellent adsorption capacity and self-healing ability. The corrosion inhibition effect is related to the concentration of the inhibitor. There was a competitive adsorption relationship between 8HQ and [Cl−], and the adsorption morphology was obviously affected by the concentration of [Cl−]. At the lower concentration of NaCl solution, the adsorption of 8HQ was more orderly, faster, and the adsorption amount was larger, which led to the formation of a denser protective layer. Density functional theory (DFT) results showed that the most stable adsorption configuration of 8HQ was NO-Top. N and O atoms are the active sites, and there is a strong coupling between them and Mg atoms, which is consistent with the experimental results.